This invention relates to combine harvesters and the like and more particularly to a device for monitoring the grain loss during the harvesting operation.
A combine harvester or similar machine used to harvest grain is provided with means to vary the ground speed so that different crop conditions may be accommodated. There are many factors affecting the harvesting of the crop such as varying moisture content, varying quantity of grain and straw, the height of the crop and the general quality of the grain.
Each combine machine, of course, has an ideal operating speed for any particular crop condition and this speed is determined by the feed rate, the conveyor rate, the concave width and the straw walker assembly design.
At one particular ground speed, the combine is capable of recovering the highest percentage of grain for that particular crop condition under which it is operating and this speed is normally determined by an operator who, depending upon his experience, visually judges the crop conditions and knows the various adjustments and capabilities of his machine.
However, it will be appreciated that crop conditions can vary widely in the same field so that it is necessary for the operator to constantly vary the speed of his machine in order to attempt to maintain the machine at the most efficient groundspeed.
One method of measuring the efficiency of the machine under certain conditions, is to measure the amount of grain lost over the back of the sieve component and over the straw walker assembly. Such devices, however, suffer from the inability to distinguish grain from other threshed crop materials such as heads, chaff, straw and the like.